Outlook Express security update

Hi, As there are loads of internet worms on the internet right now (with more being created almost on a daily basis!) I have strived to keep my XP operating system up to date as regards security patches. The only patch that I haven't installed is KB 837009 which is for Outlook Express. I don't use Outlook Express as I use AOL's e-mail service but I was just wondering if it is advisable to install the patch anyway or is there only a risk if I actually use Outlook Express?